Aclass has 18 girls. Girls make up 60% of the class. How many students are there in the class?

1 Answer
EZ as pi
Oct 19, 2016

#30# students in the class.

Explanation:

There are several which in which we can approach this question:

We can do this question using direct proportion.

"If 18 girls represent 60%, how many students represent 100%?"

#18/60 = x/100#

#x = (18xx100)/60#

#30# students altogether.
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We can make and solve an equation.
Let the number of students be #x#

"60% of the students are 18 girls"

#60/100 xx x = 18#

#x = 18 xx100/60#

#x = 30# students
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We can increase the number of girls in the ratio #100:60#

#18 xx 100/60 = 30# students

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In each case the calculation is the same, but there is a different approach and different reasoning.

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